1. Field of the Invention
This invention is related to a template that is used to mark openings in a wall or partition for electrical boxes. More specifically, this invention is intended for use in marking openings for xe2x80x9cold workxe2x80x9d boxes of the type that can be attached directly to a partition or drywall. This invention is also directed to templates for markingssingle and dual gang boxes for applications in which additional branch wiring components are to be added and for the installation of local area network components in an existing structure.
2. Description of the Prior Art
When used with reference to the installation of electrical systems and wiring in buildings, the term xe2x80x9cold workxe2x80x9d refers to the installation of additional components to existing wiring or electrical systems or to the installation of additional wiring and components in an existing structure. The most common example is the installation of a new electrical outlet along a preexisting electrical branch. Since the existing wiring is normally located behind a wall or partition, such as drywall, an opening must first be cut in the desired location. Normally this location is chosen to provide access to the wires behind the drywall or other partition. To comply with applicable codes, an electrical box must then be. inserted into the opening. Since it is most unlikely that the newly formed opening will be in a position in which the newly installed box can be attached to a stud or other structural member, some means must be provided to attach the electrical box directly to the drywall or other partition.
A number of so-called xe2x80x9cold workxe2x80x9d electrical boxes include a screw mounted tab that can be rotated into position behind the drywall after the xe2x80x9cold workxe2x80x9d box has been inserted into the new opening. These tabs are normally mounted on a screw that is accessible from the front of the box. When the xe2x80x9cold workxe2x80x9d box is initially inserted through the wall opening, the tab is located in a retracted position in which the tab lies along an external face of the box. Normally tabs are located on the top and bottom of the xe2x80x9cold workxe2x80x9d box. After the box has been inserted, the screws to which the tabs are attached are rotated. The tabs are rotatable through an arc of ninety degrees. The face of the box provides a stop in the retracted position and a ridge extending at right angles to the box wall provides a second stop against which the tab abuts when rotated to the extended position. When in the extended position, the tab engages the area around the edge of the opening in the drywall.
Most of the xe2x80x9cold workxe2x80x9d boxes of this type are plastic or nonmetallic. In the most commonly used nonmetallic xe2x80x9cold workxe2x80x9d box, the tabs protrude from the top and bottom faces of the box even in the retracted orientation. Therefore, the opening in the drywall must provide clearance for the tabs, but it must not be so large that the tabs will not engage the dry wall along a length sufficient to adequately secure the xe2x80x9cold workxe2x80x9d box. Other commercially available boxes of this type include a step in the top and bottom wall so that a rectangular opening will provide clearance for the tab. This configuration, however, reduces the interior volume of the box. Examples of old work nonmetallic boxes include CARLON plastic boxes manufactured by Lamson and Sessions, old work plastic boxes manufactured by SLATER, and boxes manufactured by Allied Moulded of Bryan Ohio. Old work style boxes are also described in U.S. Pat. No. 3,966,152; U.S. Pat. No. 4,304,957; and U.S. Pat. No. 5,434,359.
In addition to these standard nonmetallic xe2x80x9cold workxe2x80x9d boxes, there are some metallic xe2x80x9cold workxe2x80x9d boxes. These metallic versions generally include tabs located on the sides of the box that are outwardly deflected by screws or spring tabs that extend beyond the sides of the boxes.
xe2x80x9cOld workxe2x80x9d boxes are not confined to standard single gang boxes that have an internal volume of approximately fourteen to eighteen cubic inches. In some applications, dual gang boxes, suitable for mounting two electrical devices are employed. xe2x80x9cOld workxe2x80x9d dual gang boxes have an internal volume of approximately twenty-five to twenty-eight cubic inches and have rotatable tabs at diagonally opposite corners of the top and bottom faces.
Although xe2x80x9cold workxe2x80x9d boxes are commonly employed to add electrical devices to conventional wiring branch circuits used rated at 12 VAC, they can also be used for installing low voltage or class 2 wiring components. Applications of this latter type have become increasingly prevalent due to the installation of local area network computer systems. In these applications, xe2x80x9cold workxe2x80x9d boxes are located as needed for network outlets and the low voltage cables are fished behind the pre-exiting wall partitions, commonly drywall. Installations of this type are needed not only to upgrade existing office complexes, but are also required in many manufacturing applications. However, aesthetic considerations dictate, especially in offices, that the outlets using these xe2x80x9cold workxe2x80x9d boxes be neat. If the boxes are not installed so that they are level, faceplates that are subsequently screwed to the boxes will not be level. If the openings through which the xe2x80x9cold workxe2x80x9d boxes are to be inserted are excessively large, undesirable cracks may be visible around the edges of the faceplates or it may be necessary to fill in these cracks as part of a labor intensive, and therefore expensive operation. Therefore it is important that some means be provided for cutting openings that are level and that are as small as possible so that the xe2x80x9cold workxe2x80x9d boxes can be securely mounted and so that no cracks are visible after installation of a faceplate to the box.
Commonly paper templates are supplied with xe2x80x9cold workxe2x80x9d boxes to permit an installer to mark the shape of the opening into which the box will be inserted. However, these paper templates provide no means for squaring the opening so that the sides with be vertical and the top and bottom horizontal. In other words other tools are necessary to level the template, an many installers merely eyeball the orientation of the template and the resultant opening. Another means of cutting openings in drywall is to employ a template that allows an installer to either trace the location of the opening or to cut the opening using a drywall cutter or zip tool. Examples of these prior art templates are shown in U.S. Pat. No. 4,793,069 and in U.S. Pat. No. 5,222,303. The later patent includes both horizontal and vertical levels to orient an opening the size of a single gang box in a vertical orientation. That device also employs an extension for locating the box at an outlet box height relative to a floor. However, that template is bulky and is not suited to orienting boxes in vertical or horizontal orientations, and being primarily intended for use with conventional duplex outlets, is not suited for mounting boxes in tight locations. Furthermore that device only provides a template for a single gang box. U.S. Pat. No. 4,793,069 does provide templates for both single gang and dual gang boxes, but because the box opening is defined by the edges of two separate internal openings in a flat plate, that template is also rather bulky and is not suitable for all uses of xe2x80x9cold workxe2x80x9d boxes.
Therefore a template that is suitable for marking either single or dual gang boxes in various locations, both for installation of additional components on existing. wiring, and for installing new wiring systems, such as local area networks, is needed. This template should be especially suited for use in installing xe2x80x9cold workxe2x80x9d single or dual gang boxes. The template should also be easily gripped and manipulatable, and it should be easy for an installer to position the template and various orientations and positions while still maintaining the template level or perpendicular to a plumb or horizontal line. The template should also be inexpensive to manufacture and should use conventional off the shelf bubble type levels to permit an installer to properly orient the template.
These objectives can be realized by employing a template for use in cutting an opening in an existing wall for installation of an old work electrical box. The template comprises a plate having edges defining the shape of an opening through which an old work electrical box can be inserted. The plate includes spaced apart gripping protrusions extending beyond a front surface and a level positioned between spaced gripping surfaces so that the template can be oriented relative to a plumb line.
This template for use in outlining an opening in a panel for installation of an old work electrical box in a panel comprises a plate having a width equal to the width of a dual gang old work electrical box opening with sections along a top and a bottom edge protruding from adjacent edge sections to define areas for clearance of an old work dual gang electrical box latch for insertion therein. The plate includes an additional section along one of the top and bottom edges with a horizontal slot extending through the additional section for defining a portion of the opening adjacent to the protruding section along the one top or bottom edge. The plate also includes at least one vertical slot so that the vertical slot is spaced from one side of the plate by a distance equal to the width of a single gang old work electrical box, the additional section along the top or bottom edge of the template defining an opening for clearance of an old work single gang electrical latch.
This template compriseia tool for use in cutting a hole in a wall for the installation of an electrical box. Templates for xe2x80x9cold workxe2x80x9d and new boxes would employ many of the same features with the periphery of the template being defined by the specific application. The tool comprises a flat member having peripheral edges, the peripheral edges being dimensioned to define a dual gang box opening,. A portion of the peripheral edges also are dimensioned to define a portion of a single gang box The flat member has at least one slot, the slot defining a remaining portion of the single gang box opening.